HtmlTextWriter.OnAttributeRender 方法

protected:
 virtual bool OnAttributeRender(System::String ^ name, System::String ^ value, System::Web::UI::HtmlTextWriterAttribute key);

protected virtual bool OnAttributeRender(string name, string value, System.Web.UI.HtmlTextWriterAttribute key);

abstract member OnAttributeRender : string * string * System.Web.UI.HtmlTextWriterAttribute -> bool
override this.OnAttributeRender : string * string * System.Web.UI.HtmlTextWriterAttribute -> bool

Protected Overridable Function OnAttributeRender (name As String, value As String, key As HtmlTextWriterAttribute) As Boolean

參數

傳回

一律為 true。

範例

以下程式碼範例說明如何覆寫該 OnAttributeRender 方法。 如果已渲染屬性，但Size值未Size被渲染，覆寫會30pt呼叫OnAttributeRender該方法加入AddAttribute屬性並將其值設為 Size。30pt

// If a size attribute is to be rendered, compare its value to 30 point.
// If it is not set to 30 point, add the attribute and set the value to 30,
// then return false.
protected override bool OnAttributeRender(string name,
    string value,
    HtmlTextWriterAttribute key)
{

    if (key == HtmlTextWriterAttribute.Size)
    {
        if (string.Compare(value, "30pt") != 0)
        {
            AddAttribute("size", "30pt");
            return false;
        }
    }

    // If the attribute is not a size attribute, use
    // the base functionality of the OnAttributeRender method.
    return base.OnAttributeRender(name, value, key);
}

' If a size attribute is to be rendered, compare its value to 30 point.
' If it is not set to 30 point, add the attribute and set the value to 30
' then return false.
Protected Overrides Function OnAttributeRender(name As String, _
    value As String, _
    key As HtmlTextWriterAttribute) _
As Boolean

    If key = HtmlTextWriterAttribute.Size Then
        If [String].Compare(value, "30pt") <> 0 Then
            AddAttribute("size", "30pt")
            Return False
        End If
    End If

    ' If the attribute is not a size attribute, use
    ' the base functionality of the OnAttributeRender method.
    Return MyBase.OnAttributeRender(name, value, key)
End Function 'OnAttributeRender

備註

該方法的HtmlTextWriterOnAttributeRender類別實作總是回傳 true。 OnAttributeRender覆寫可以決定屬性是否會被渲染到頁面上。

給繼承者的注意事項

如果你是從 HtmlTextWriter 該類別繼承，可以覆寫 OnAttributeRender(String, String, HtmlTextWriterAttribute) return false 的方法，以防止屬性被渲染、無法渲染到特定元素，或是針對特定標記被渲染。 例如，如果你不希望衍生物件HtmlTextWriter將屬性渲染bgcolor到<table>元素上，你可以覆寫 並在 OnAttributeRender(String, String, HtmlTextWriterAttribute) 通過falsenamebgcolor時回傳TagNametable屬性值。

另請參閱

• TextWriter
• HtmlTextWriterAttribute